Telegraph



J. N. CORREIA.

TELEGRAPH.

APPLICATION man OCT. 23. 1918.

1,434,773., Patented Nov. 7,1922

/n 1/6 n/or J05 /V Carma/'0 a W i v l a i aoiio 1v. conzania, or new roan, N. Y., assieivon T0 wnsrnnn ELECTRIC COMPANY,

incoaronarnn, or new. roan, n. a conroaarron or new roan.

TELEGRAPH.

Application filed October 23, 1918.

To all 10710111 may concern: A

it known that I, Jofxo' N. CoRnnIA, a citizen of lortu'gal, residing at New York, in the countyot New York, State of New York, have inventeiil certain new and useful .l'n'iprovenicnts in Telegraphs, oi which the :lollowing is a full, clear, concise and exact description.

This invention relates to telegraph systems and more particularly to systems ot cable tclegraphy.

The principal object of this invention is to provide any improved'nicthod of trans mission and organization oi apparatus for preventing so-called wandering Zero in telegraph line conductors having high electrostatic capacity characteristics.

The present invention is adapted particularly to the transmission of messages according; to the Ba-udot and similar codes made up of permutations and combinations ot positive and negative polarities wherein the cl'iaracter oi? an impulse is controlled by the character of the preceding impulse.

ll herever, in such codes, a plurality of successive impulses ot the same polarity would normally occur, the present invention provides that but a single short impulse shall be sent to the line and that following; such impulse the line shall. be grounded until a reverse impulse occurs.

The invention also provide. that the potential of each impulse shall depend upon, and be governed automatically by the duration oil the grounding interval immediately precedingand the one immediately suc- (peding. i

T his invention is illustrated diagramniaticallv in the accompanying drawing, in which Fig. 1 serves to illustrate a transinitting system suitable for practicing the fealures of this invention. in Fig. 2 is illustratel inqrraphic t :m the potential and polari v relation of' leetinp; currents as ordinarily a'oplied at the 3 there graphically represented the ntial and polarity relation of the ind-- prses illustrated in Fig. actually ap plied. to a line conductor through the operation of the present system.

in describing this system the general principle of its operation will first be considered.

Accordingly, this invention provides that line comluctor may he energized during a 'nnpulse groups of se ding: end of a line conductor. while in Serial No. 259,322.

be connected to the earth. It is further provided in the transmission of groups of character selecting impulses characterized by perinutations of impulses of difi'erent current p( )larities as in the well known code of Baudot, that following a succession of impulses 011 like polarity the potential or a next succeeding impulse of opposite polarity will be predetermined by the potential and duration of the previous impulses, and in accordance with such predcterrnination, current of proper polarity for a succeeding impulse will be automatically selected from a plurality of current supply points having diiicrent potentials. A combination of ac tualpotential values which were determined and employed in actual tests have been indicated in the, drawing in order to facilitate a more detailed description of the system which will presently he proceeded with.

Under the assumption that a single impulse may be referred to as a short interval, while two or more successive impulses of like polarity may be referred to as a long interval. the u; ieral relation of the potentials and polarities, one to another may he briefly set forth follows:

l l hen a short interval followsa short interval the current therefor should have a PGllL ial of 100 volts; in case a long interval follows a short interval, the currentshould have a potential of 66 volts; when a short interval follows a long interval, the current should have a potential of volts and when a long interval follows a long interval the current should have a potential of 4.0 volts.

The foregoing values were, of course, obtained overa cable having certain electrical time constants or elect characteristics with respect to the potentials indicated, while the devices at the receiving station at which the impulses were manifested were also of proper electrical. time constant relation with respect to the transmitted potentials and the time constant of the cable. Therefore, it will be understood that while these values are true for a given. situation, other or diii'erentwalues may be necessary in arriving); at the proper potential values for'any other cable transmission condition. ln. :1 more detailed description of this eyecent these transmitting levers are connected to oppositely poled and grounded direct currentsources 21 and 22, respectively, while the transmitting. levers connect respectively to segments 11 20 or the distributor. Al though this distributor has, for convenience of description, been shown in developed form it will .be un'derstood that it may be of suitable circular construction to provide that three trailer or c'ont actor arms 25, 41 and 61 may travel from left to right over the segments ll--20 and the respectively adjacent collector rings 26, a2 and 62. In operation, the brushes should continue spaced or positioned substantially as shown in the drawilw, with respect to each other. Brush arm 2a in passing over a segment which may be energized with positive cur rent from the source21, establishes this current with the collector ring 26,.tr0m which the current may traverse a conductor 2?,the windings of two serially connected polar relays 28 and 31 and a resistance unit 34, to earth. As indicated by the conventional plus and minus signs adjacent the armatures of these relays, a positive impulse should cause these armat-ures to assume the positions in which they are shown in the drawing, while in a converse manner the brush 25 on encountering a. segment'negatively energized from the source 22 should establish such current through the path al ready traced, to cause the armatures-of the r'eh 5s and 31 to assume their respective left-hand bias which is opposite to the positions in which they are shown in the, drawing. The relays 28 and 31 respectively serve to'select di'lferent potentials of negative and positive currents as may have been previously selected by two polarized relays (it The distributor brush etl contr'olsthe inclusion of either positive or negative currents as may bepresent on the segments lie- 510 through selections effected by the levers ll0 from the sources 21 and 22 with a collector ring: 42 which is connected by means of a conductor 43 in branch relation through the windingsof two polar relays 44 and 47. In series with the relay at there is provided a resistance unit and a condenser 5.1, while a. resistance unitv 52 and a condenser 53 are similarly connected in series with the relay H. The presence ot the condensers 5i and 53 in the operating circuit of these rela s, render the currents supplied by the brushell of momentary effect only, and since these relays are biased ii'ldicated, to normally retain their armatures in the: positions in which they are shown in the drawing, an impulse of positive cu'rreiit' will cause the relay in to mementarily separate its contacts l5 and to close its contacts all, while the same impulse will 'not'a ff'ectthe relay ll, except to additionally stress its armature in maintaining its contacts 458 closedl In a converse manner an impulse of negative current supplied through the bru'sli'al would cause the relay at? to nioi'ne'ntarily separate its contacts 48 and. to close its contacts 49. while, the armature of the relay 44 would continue on its normal bias in establishing its contacts 45'. It will therefore beclear that a line conductor ll connected to the armature of the relay -17 is normally connected by way oi the contacts 18 of the relay 4L7. and the contacts if) of the relay at, to earth. Since the contacts a9 0f the relay 4;? control a connection-extending to the armature of the selectively' controlled switching relay 28 it will be, oli viousithat during any instant the relay a7 may be operated its contacts 49 will connect the line conductor L througheither the contacts 29 or the contacts 30 of the relay 28 to receive negative current of, such potential as may have been selected through either one or another of the contacts 65,66 or ($7, and 68 of the latter relay. In a corresponding but inverse manner, momentary responses oi the relay 44 to impulses of posithe current will connect the line by Way of the contacts 48 of the relay a7 and the con tacts 46 of the relay a l to the armature ot the positive-current selecting relay 31, whence positive current having. a potential as previously selected by the relay 74, may become effective with the line L.

The brush 61 in traveling through its path, successively joins the segments 11-20 with a collector ring 62 and in accordance with prepared energizations of these segments by way of the transmitting contacts 1-10 such currents may traverse a conductor 62), the serially connected windings of the polar relays ('34: and 74: and a resist ance 70 to earth. For convenience of illustration: each of the latter relays has been provided. with two arinatures which are similarly acted upon by any current through the associated relay windings, and as indicated the. plus and minus signs adjacent the armatures of theserelays, a positive impulse should establish biasing to close the contacts 65 and 67 of therelay Get and to close the-contacts 7 and 770i the relay 74;

In asimilar but converse manner, theefieet of a ne ative impulse ofcurrent applied to these relays through the brush 61 should cause the relay (5 1 to close its contacts 66 and 68, while the relay Tel will close its contacts 7 6 and 78. It will be mentioned that a condenser 71 connected in parallel with the resistance unit 70 and a condenser 35, similarly connected in parallel with the resistance unit 84 0f the operating circuit of the relays 28 and 31, are for the purpose of providing capacity which may be adjusted in connection with the respectively associated relay circuits in such a manner that any desired elfects with respect to the time constant relation ot the relay circuits may be secured.

in order to illustrate an actual appliczn tion cit different potentials to the line conductor l) in accordance with this invention, a transmission example will now be assumed and the various operations or steps necessary in disposing of such a combination of impulses will be traced and considered in detail. Therefore, as illustrated'by the polarity line 80 in Fig. 2 of the drawing, let it be asslnned that for the channel A a combination of impulses will be prepared in the order ot a first and second positive impulse, a third negative impulse, a fourth. positive impulse, and a fitth negative impulse, while for the second channel B a combination comprising a first negative i1npulse, a second, third, and fourth positive impulse, and a fitth negative impulse will be prepared. For such impulse combinations the transmitter levers 1, 2, 4, 6 and will stand in their respective forward positions, which are opposite to the positions in which they are shown in the draw inn, while the levers 3, 5, 7, 8 and 9 will stand in their respective normal positions which .is the position in which they are shown in the drawing. Assuming now that the relays 28, 31, 64: and 7 willbe positioned s shown in the drawing, due to the brushes and (51 having respectively encountered positivelypoled segments in other distributor quadrants or channels not shown.

The brush 25 on arriving over the segment 11 will establish positive current from the source 21 over the circuitalready traced, to retain the relays 28 and 31 in the positions in which they are shown. and since the transmitter contact 2 is also connected with the source of positive current at this time, these polar relays will continue on the same bias during the time the brush is also passing over the segment 12. (in arriving over the segment ll. the brush C1 will es tablish positive current over the circuits already t'aced to momentarily operate the relay 4:4. This establishes a circuit which may be traced from the line conductor L through the contacts 48 of the relay 47. the cmitacts 4% of the relay in. the contacts 32 ot the relay 31, and the contacts 7'? of the relay Tl to a positively poled and grounded source of current having a potential of 66 volts, as indicated in. the drawing. Since the impulse combinations assumed for the transmitter contacts 110 corresponds with the shaded line 80 in Fig. 2 of the drawing reference may be had to Fig. 3 oi? the dra ing wherein the shaded line intervals represent in a theoretical form the actual moments during which the line L may be energized under the transmission of the prepared impulse combinations. The lines paralleling spectively designated as 100 66 etc. to correspond with the various potentials of the currents employed in illustrating this system. Therefore the first impulse of positive current just traced to the line L will correspond with the first or left hand impulse further identified as of positive polarity and having a potential of 66 volts. At the time this impulse becomes efiective with the line L, the brush 25 will be passing over the positively energized segment 12 and accordingly relays 28 and 31 will continue biased as shown. On the brushes advancing to the next respective segments negative current from the source 22 to the segment 13 may traverse the brush 25 to negatively bias the switching relays 28 and 31, while the brush 41 now over the positively ener- ,L ized segment 12 will be non-effective to again operate the relay 4A for the reason that the condenser 51 retains the positive charge which continued during the time the brush 41 was traversing the positively energized segment 11. In substitution of a current impulse the line conductor L will therefore continue grounded through the contacts of the relays 14 and 47 during the interval corresponding with the second impulse of the assumed combination. Arriving at the next position, the brushes 25, 4:1 and 61 will be over the segments LL13 and 11, respectively. The brush. 25 now joins the positively energized segment 14 to correspondingly bias the relays 28 and 31, while the brush 61 in connecting the posi tively energized segment 11 tothe relays 64: and 74 doesnot affect these relays which now stand biased to their positive positions as already described. At this time the brush t]. therefore join the nega tively poled segment 13 to momentarily opcrate the relay 4?, thereby completing a circuit which may be traced. from the line conductor L by way oi the contacts 49 of the relay 47, the contacts 29 ofthe relay 28, and the contacts 67 of the relay 64lto a source of negative current having a potential of volts, as indicated in the drawing. On the brushes advancing'to the next segments 15, 14: and 12, respectively, the brush 25 causes the relays 28 and 31 to be nee-a tively biased while the relays 1- will be opthe zero line 0 (Fig. 3) are re retain the relays-28 and erated to momentarily connect the line I. by way oi: the contacts oi the relay l? over the contacts 16 of the relay tl'ience thron the contacts 38 of the relay 31 and the contacts of the relay 74lto a source of positivei ool'ed current indicated haw a peter il 01'? 100 volts. The )rush (ll. at this time applies positive current from the segment 12 through the relays and 7-1 and these relays will therefore remain on their present positive bias. On arriving over the segment 16 the brush 25 again encounters negative current and the relays 28 and 31 will accordingly continue on their present negative bias, while the brush 61 now establishes negative current from the segment 13 to oppositely or correspondingly bias the relays 6i and 7%. The brush 41 at this instant connects negative current from the segment 15 to momentarily operate the relay 17 to close'its contacts 49, thereby switching the line conductor L to a circuit which extends through the contact or the relay 28 and the contacts 66 of the relay Gt to a source of negative current havii a potential of 66 volts, as indicated. This impulse being; the fifth or last impulse of the selecting combination for the first channel A the transmission of the character selecting combination for this channel will be completed ther by. On the brushes arriving over the segments 17, 16 and 14, respectively, current from the positively charged segment 17, over the brush 25 will bias the relays 28 and 31 to the positions shown in the drawing, positive current from the segment 14 over the brush 61 will correspondingly bias the relays 6a and 7 1 while negative current from the segment 16 over the brush 11 will be noncfiective to operate the relay 47 since the condenser 53 stands charged with negative current received durthe time the brush 61 was traversing the negatively charged segment 15, therefore no energization of the line conductor take place duringthis first impulse interval of the impulse combination for the second channel but instead, the line conductor continues grounded, as already traced. When the brushes respectively arrive over the segments 18, 17 and 15, positive current from the segment 18 will act over the brush 25 to 31 on their present positive bias. Negative current from the segment15 will be established over the brush 61 to negatively bias the relays G l and 7% while positive current from the segment 17 may act, over the bro 1:1 to energize the relay 44, thereby connecting' the line conductor L through the contacts of the relay 417 by way oi the contacts 16 of the relay 44, the contacts 32 01. the relay 81 and the'contacts 7 Sci the relay 74C to a source of positively poled current indicated as having a potential of 40 volts. For the next or third may/re 19 to positively bias the relays 28 and 31',-

while the brush 6-1 will apply negative current from the segment 16 which w ll not alfect the relays Gel and 7 4;- on their presentnegative bias. The brush 41 now establishes positive current from the segment 18 with the'relay 44. This relay will not be attlected by this current, however, since its associated condenser 51 is already charged with current 01" this sign as previously received while the brush 41 was over the segment 17. The line conductor L will therefore continue grounded, as already described, during this third impulse interval. For the fourth impulse the brushes will be respectively over the segments :20, 19 and 17. Negative currents from the segment 90 over the brush 25 will correspondingly bias the relays 28 and 31, while positive current from the segment 17 over the brush 61 will correspondingly bias the relays (S1- and 74:. The brush L1 now establishes positive current from the segment 19 which encounters a positive change in the condenser 50 due to the current from the segments 17, 18 and 19 similar to the efiects already described. Therefore the cable continues grounded dur the period corresponding with the fourth impulse interval. In transmitting the fifth or last impulse for the present combination 0i the second channel, the brush 25 will have advanced to the first segment in a third channel (not shown) and, "for convenience oi illustration in carrying out the operations for the present combination, let it be assumed that such segment of the third chan. nel would be energized with positive. cur rent to act over the brush 25 in positively biasing the relays 28 and It will be pointed out that the combinations of impulses assumed. for the two channels happen to be of such relation that in case the distributor consisted of only the two channels shown and that the segmentsQO and 11 would be adjacent in forming; a segmented ring the brush 25 would be over the segment 11 at this moment and assuming for pur pose of description that the set up of the combination considered is still present in the first channel this brush would accordingly receive the necessary positive current from the segment 11. At this time positive current from the segment 18 traverses the brush 61 and retains relays (it and 74: on their present positive bias. Negative current from the segment 20 may now traverse the brush 41 to energiize the relay l7, thereby completing a circuit from the line conductor L which may be further traced through the contacts 49 of the relay 47, the contacts 29 of the relay 2S and tliecoiitacts 67 of the relay 64 to the source of negatively poled current having a potential of 50 volts. By inspection of Figs. 2 and 3 of the drawing it will be seen that the assumed impulse combinations, as illustrated in Fig. 2, would have required 10 impulses of current but in the actual transmission operations, wherein grounding of the line conductor was substituted tor successively recurring impulses of the same polarity only SlX impulses of current were actually imparted to theline conductor, the line continuing grounder during all periods intern'iediate such actual momentary inclusions of current therewith. It will also be clear that the condensers 5i and 53, as connected serially in the operating circuits oi? the relays 4A; and 45?, respectively, serve to render the current ell'ects with these relays as established by the brush 4L4. only momentarily etliective to move the arinatures to their forward positions and since the operating circuits of these relays are connected in parallel, one with the other with respect to the energizing lead d3, the condensers 51 and 58 will always receive and retain current charges of like polarity and, therefore, these condensers cannot discharge accumulatively one condenser with the other. It will also be understood that the speed of the distributor may be sufliciently hi gh with respect to the spacing elf the ments to prevent any appreciable leaking "from the condensers during the time the brushes 25 and 4:1 arepassing from one segment to another. This feature, relative to the connective relation oi? the coniilensers, prevents operation of either one oi? tie re lays 4A and 4E7 during impulse intervals coraesponding with successive repetitions of impulses of current of like polarity.

What is claimed is:

1. The method of telegraphy which consists in alternately energizing and grounding a line conductor and in varying the value of the potential strength of said line cnergizations by gradations in a predeterniined manner.

The method of telegraphy which consists in alternately energizing and grounding a line conductor and in varying the potential strength of said line energizations in a predetermined manner with respect to the duration of the groundings of said line.

3. In a telegraph system, a line circuit, means for alternately energizing and grounding said line, and means for varyin the value of the potential strength by a plurality of gradations in a predetermined manner.

4;. In a telegraph system, a line conductor, means for alternately energizing and grounding said line, and means for varying the potentialstrength of said line energization in accordance with the duration of a preceding ground interval.

A. telegraph system in combination with a signaling conductor, means for preparing predetermined combinations of cur rent impulses, means for impressing said impulses on said signaling conductor, and further means controlled jointly by the polarity of the impulse immediately precedingand the second. impulse succeedin each impulse for determining the potential strength of such impulse.

6. In a telegraph system, a line conductor, a plurality of sources of current having dif- :lierent "potential strength, means for preparing predetermined combinations of cur rent impulses, electroresponsive'means controlled by said impulses for alternately ener gizing and grounding said line, and means selectivelyoperated for includin with said line conductor one of said sources of cur rent.

7.. In a telegraph system, tape controlled transmitting contacts, means for preparing permutations oi current polarities at said contacts, a first pair of oppositely responding polar relays, distributor means for rendering said contacts effective in controlling said relays, a positive and a negative current source each having several selectively different potentials, a second pair o1 relays controlled by said distributor for selecting predetermined potentials and polarities from said sources, a third pair of relays controlled by said distributor for applying potentials selected by said second pair of relays to be controlled by said first pair of relays, and means controlled by said firstpair of relays for alternately energizing and grounding said line circuit.

8. In a telegraph system, a line, means for preparing predetermined combinations of current impulses, a distributor, a plurality of sources of current of different polarities and strengths, a plurality oi? relays having their armatures normally? connected with said line and controlling the energization thereof, means associated with said relays for effecting the gI'OUIlClil'lg of said line in substitution of successively recurring impulses of the same polarity, and means controlled by said distributor for impressing on said line a current impulse following a ground interval the potential strength of which is dependent upon the duration of such ground interval.

In witness whereof, I hereunto subscribe my name this 18th day of October A. 1)., 1918.

Jolie u. coins-uni. 

